In order to deflect a plurality of charged particle beams, a deflector including a semiconductor chip having through holes passing the charged particle beams is used. Each through holes has a pair of electrodes, and each charged particle beam is independently deflected by an electric field applied between the pair of electrodes.
The semiconductor chip may be bonded onto a substrate having openings corresponding to the through holes. It is required to arrange the through holes with a high positional accuracy so that the plurality of charged particle beams pass through the through holes.